Re: [PATCH v7 2/5] platform/x86: int3472: tps68470: fix clock consumer registration for Dell Latitude 5285
Andy Shevchenko <[email protected]>
| Newsgroups | org.kernel.vger.linux-media,org.kernel.vger.linux-kernel,org.kernel.vger.platform-driver-x86 |
|---|---|
| Organization | Intel Finland Oy - BIC 0357606-4 - c/o Alberga Business Park, 6 krs, Bertel Jungin Aukio 5, 02600 Espoo |
| Message-ID | <[email protected]> |
On Wed, Aug 19, 2026 at 04:01:04PM +0200, Thierry Chatard wrote:
> The BIOS on the Dell Latitude 5285 leaves GNVS field C0TP at zero.
> With C0TP=0 the ACPI _DEP method on INT3479 (OV5670, front camera)
> resolves to PCI0 instead of the INT3472 (TPS68470 PMIC) device.
>
> Because for_each_acpi_consumer_dev() walks the _DEP reverse-mapping,
> INT3479 is invisible to it: the clock consumer lookup entry for the
> front camera is never registered with the tps68470-clk driver, and
> the OV5670 sensor driver cannot acquire its MCLK.
> Fix this without touching ACPI tables by adding optional static clock
> consumer fields to struct int3472_tps68470_board_data:
>
> unsigned int n_clk_consumers;
> const struct tps68470_clk_consumer *clk_consumers;
No need to repeat what we may read in the code.
Is this message constructed with a help of AI?
The rule of thumb: use AI as a tool, do not blindly
copy'n'paste what it pukes.
> When board data is present and n_clk_consumers is non-zero, probe uses
> the static list instead of for_each_acpi_consumer_dev() to populate
> tps68470-clk platform data. Platforms that do not set these fields
> continue to use the existing ACPI traversal path unchanged.
...
> + struct gpiod_lookup_table * const *tables;
Okay, you want the outer pointer to be const, that's probably fine, but in any
case the GPIOLIB modifies the given tables.
> int n_consumers;
> int device_type;
> int ret;
> - int i;
> + unsigned int i;
Keep the reversed xmas tree ordering.
...
> + /*
> + * The order of the cells matters here! The clk must be first
> + * because the regulator depends on it. The gpios must be last,
> + * acpi_gpiochip_add() calls acpi_dev_clear_dependencies() and
> + * the clk + regulators must be ready when this happens.
> + */
> + cells[0].name = "tps68470-clk";
> + cells[0].platform_data = clk_pdata;
> + cells[0].pdata_size = struct_size(clk_pdata, consumers, n_consumers);
> + cells[1].name = "tps68470-regulator";
> + cells[1].platform_data = (void *)board_data->tps68470_regulator_pdata;
> + cells[1].pdata_size = sizeof(struct tps68470_regulator_platform_data);
> + cells[2].name = "tps68470-gpio";
> +
> + tables = board_data->tps68470_gpio_lookup_tables;
> + for (i = 0; i < board_data->n_gpiod_lookups; i++)
> + gpiod_add_lookup_table(tables[i]);
I'm wondering if we can / want to use gpiod_add_lookup_tables().
> + ret = devm_mfd_add_devices(&client->dev, PLATFORM_DEVID_NONE,
> + cells, TPS68470_WIN_MFD_CELL_COUNT,
> + NULL, 0, NULL);
> + kfree(cells);
> +
> + if (ret) {
> + for (i = 0; i < board_data->n_gpiod_lookups; i++)
> + gpiod_remove_lookup_table(tables[i]);
> + }
...
> const struct int3472_tps68470_board_data *board_data;
> - int i;
> + unsigned int i;
This change along with the similar above deserves a separate patch.
--
With Best Regards,
Andy Shevchenko